The present invention concerns novel compounds, their preparation and their use as anti-peptic ulcer medicine. More particularly, the present invention concerns novel compounds of 2-substituted-phenyl-5-alkylthiazolidine-4-one which are useful as anti-peptic ulcer medicines.
Originally, the peptic ulcer is the collapsed parts of the gastric or enteric mucosa weakened by the action of aggressive factors such as hydrochloric acid and pepsin in the gastric juice. The mild cases of peptic ulcer are curable after 3 to 4 month of hospitalization and treatment, however, the serious cases are accompanied by hemorrhage and perforation of the organ to be chronic.
As an etiological cause of peptic ulcer, the abnormalities in the autonomic nerve system and in the mucosal blood flow due to physical and/or mental stress has been considered, however, it is practically impossible to interpret the etiology of peptic ulcer unitarily because the viscera themselves are subjected to complicated control by the nerves and hormones.
Hitherto, as an anti-peptic ulcer medicine, sodium hydrogen carbonate, aluminum salts and magnesium salts have been used for a long time for neutralizing the above-mentioned acid as the aggressive factor. However, these medicines only temporarily neutralize the acid to alleviate the pain and do not accelerate the substantial cure of the ulcer.
Recently, many kinds of anti-ulcer medicines have been developed based on the presumable causes of ulcer, including the medicines suppressing autonomic nerve, that is, so-called anticholinergic agents, the agents repairing the damaged tissues and the agents improving the blood flow. However, the present situation is that none of them can be said satisfactory in view of their effectiveness or their side effects.
For instance, carbenoxolone which has been commercialized as an anti-peptic ulcer medicine has been broadly used because of its excellent accelerating effect on the ulcer-curing, however, it has an aldosterone-like side effects to cause hypertension and weakening of muscular function when taking continuously. In addition, the above-mentioned anti-cholinergic agent shows severe side effects such as mydriasis and thirst due to the blocking of the parasympathetic nerve, and it has been reported their effects of accelerating the ulcer-curing is low.
Since it generally takes a long time period for curing the peptic ulcer, the period of administration of an anti-peptic ulcer medicine extends to 100 to 150 days on the average and to one to two years in some cases. And accordingly, it is required that the anti-peptic ulcer medicine is highly safe as well as highly effective in ulcer-curing.
An object of the present invention provides an anti-peptic ulcer medicine excellent in anti-peptic ulcer action and pharmacologically safe.
Another object of the present invention provides a compound useful as an anti-peptic ulcer medicine.